CSKA Moscow director Roman Babaev says West Ham owe them €18m for the signing of Nikola Vlasic and have warned they could be blocked from signing players if they don't pay up.

Vlasic is currently on-loan with Torino.

And Babaev says they now have precedent after winning a similar case against Japanese club Vegalta.

He told Sport-Express: "Having exhausted all the ways of amicably resolving this issue, we turned to the FIFA Dispute Resolution Chamber.

"Unfortunately, they're inundated with such claims and is not considering them as quickly as we would like.

"We expect a ruling in a month.

"They owe about €18m. A similar case was considered in relation to our lawsuit against the Japanese club Vegalta, to which (Takuma) Nishimura moved. The Japanese at first basically refused to pay us. As a result, having reached CAS, we proved our case. Vegalta was ordered to pay CSKA the amount due.

"However, the Japanese referred to the fact that, in view of the international situation, sanctions against Russia, the payment was unrealistic.

"Then we turned to FIFA. The case was considered for a long time, but the decision was made in our favour. Vegalta is now prohibited from registering new players until the settlement with CSKA. Another thing is that FIFA allows one reservation in such cases."

Babaev explained: "Only if absolutely irrefutable legal evidence of the impossibility of payment is provided, the decision can be reviewed. However, today we already have a precedent.

"It is clear that the situation with the UK is the most difficult, but we intend to go to the end and use all the methods that allow us to regulate and use the norms of the law."